The integration does not currently recognise savings goals. The balance within these goals is simply included in the overall account balance and transfers between the main account and the savings goals in Starling are not recorded in Xero. This is to ensure that the Xero account balance is an accurate representation of the Starling account balance.
As a result the balance within both the main account and savings goals should be entered into Xero as the starting balance after connecting Xero to Starling.